1. Field of the Invention
The present invention generally relates to remote management of computer servers and more particularly to a system which minimizes the hardware and software needed to remotely manage multiple servers.
2. Background of the Invention
It is becoming common for businesses to use large numbers of computer servers. For example, Internet service providers may need hundreds or even thousands of servers. Websites are operated by servers. The more successful the website, the more servers it requires. When hundreds or thousands of servers are to be located on one premises, they need to be adapted for rack mounting to save space and provide for convenient routing of power and signal cables.
Computer servers usually have the standard ports for a keyboard, a monitor and a mouse. However, servers are normally purchased and installed without such peripherals attached to each server, which would increase the equipment cost, and more importantly the space required to house the servers. It is possible to connect these peripheral devices to manage a server on a temporary as-needed basis, which involves bringing a set of peripherals (on a “crash cart”) close enough to the server to be connected. This approach is very time consuming, especially when hundreds or thousands of servers are to be managed. Alternately, KVM (Keyboard, Video, Mouse) cables from each server can be connected to a KVM switch, and a set of KVM peripherals can be connected to the KVM switch to manage a number of servers. A typical KVM switch can handle about eight servers. Multiple KVM switches can be cascaded to manage more servers than a single KVM switch can support. KVM cables are bulky and can run only tens of meters. In Data Centers housing large numbers of servers, using KVM cables and switches will allow limited remote manageability, but the installation involves so many bulky KVM cables and switches that it may be impractical for cost, space, usability and scaling.
It is highly desirable to manage servers remotely, especially from across a building, town, country, or even the world. The hardware and software for true remote management is currently available. For example Compaq Computer Corporation produces a remote management system known as Remote Insight Lights-Out Edition (RILOE). The RILOE includes a remote management module, RMM, which is available as a PCI card or chip set, which may be installed in each server to be remotely managed. Each RMM is assigned a network address and coupled by a network cable to a network switch. The switch connects the remote management modules in the servers to a network, e.g., the Internet, so that a server administrator may use a remote computer system to connect to and manage any server which is connected to the switch. The remote computer system may connect to the servers through a local network, a wide area network or the Internet. In addition to the keyboard, video and mouse console functions, the remote management functions can also include the following:                virtual devices, such as, virtual power button, virtual CD and virtual floppy        transmitting recorded video sequences, such as, last failure and last POST (Power-On Self-Test)        different log-in privileges to different remote boards        sending alerts, such as, remote boards request that the manager board send an SNMP (Simple Network Messaging Protocol) trap over the network.        
As discussed above, many businesses have hundreds or thousands of servers. Since almost all the racks to hold servers have mounting holes in 1U increments, server height dimension is typically a multiple of 1U. A “1 Rack Unit,” or in short “1U,” measures 1.75 inches. Modern low-profile servers have a vertical dimension of 1U. Therefore, a standard 42U server rack can hold a total of forty-two servers. If all the servers in a rack are to be remotely managed, forty-two remote management modules, forty-two network addresses, forty-two network cables and a switch having capacity for forty-two network lines are required for each rack. This equipment represents a significant investment. This problem is amplified multiple times as the number of servers grows in a rack. With the advent of blade servers, where server modules are vertically orientated, there can be hundreds of servers within a 42U rack.
It would be desirable to provide a remote management system for multiple servers that requires less equipment than the prior art systems.